Mobile communications systems are one of the hotspots in research in current communications technologies, and providing indoor coverage is one goal of mobile communications systems. Femto Cell, Pico Cell, and Home NodeB are the latest forms and specific applications of some mobile communications products proposed to solve the indoor coverage problems.
The Femto Cell, the Pico Cell, and the Home NodeB are all mobile communications products with low power, small-scale coverage, and can be referred to collectively as micro-base stations. Their general application scenarios are residential and the offices of middle and small-scale companies, and there are a large number of residences and offices. When a user is outside, the system provides services for the user through signals of a ordinary macro-base station; when the user enters a room or a building, the system provides better services for the user through a micro-base station.
Because of the universality of the services of the mobile communications system, micro-base stations may meet the basic demand of continuous and non-interrupting user service. In other words, roaming and handover capabilities between a common macro-base station and a micro-base station may be provided.
In a mobile communications system including micro-base stations, due to the large number of the micro-base stations, the handover between the micro-base station and the macro-base station becomes more difficult. In particular, when a user enters the coverage of a micro-base station from the coverage of a macro-base station, there may be such problems as how to transfer the information of the micro-base station to the user and enable the user to capture the signals of the micro-base station quickly in an efficient and high-speed way to achieve fast handover, and how to achieve the timely and efficient broadcast of the information of a neighboring micro-base station of the macro-base station in a mobile communications system containing numerous micro-base stations, so as to ensure the smooth handover between the macro-base station and the micro-base station.
In the present mobile communications systems, when a large number of micro-base stations/micro-cells are introduced, because the number of neighboring cells that can be included in the neighboring cell message broadcast to users by the macro-base station is limited, which is generally no more than twenty, and generally no more than 32 at the most, while the neighboring micro-cells of the present cell may be as many as several hundreds altogether, and even more than a thousand. Therefore, it is impossible to broadcast all the neighboring micro-cells of the current cell to the users.
Both of the solutions in the prior art cannot transfer the information of the neighboring micro-cells accurately and in time, and thus a fast and accurate handover cannot be achieved, which tends to result in service interruption or reduction of quality of service.